TheoreticallyNot hard to see the clear effect, but I'm not sure 1 ppm per day is a good value since reef tanks without water changes rarely accumulate 365 ppm in a year. I used 0.1 ppm per day below, but the large effect of a water change is clear, its just the values along the axis that change when making different accumulation rate changes.
Figure 2. Nitrate concentration as a function of time when performing water changes of 0% (no changes), 7.5%, 15% and 30% of the total volume each month. In this example, nitrate is present at 0 ppm at the start, and is accumulated at a rate of 0.1 ppm per day when no water is changed.
Having a daily nitrate overproduction of only 0.1 ppm/daily doing daily water changes of 1% will prevent accumulation maintaining the level at 9.7-10ppm.
Doing monthly changes of 10% the level will accumulate reaching a level of +- 27-30ppm
Doing 30% monthly the level will be maintained at +- 7-10ppm
it all depends on the nitrate overproduction which should be near O, meaning all produced nitrogen is used up.
mixed reef systems with a skimmer, feeding normal commercial fish food, 0.5- 1ppm daily nitrate overproduction may be realistic.
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